"Nanoflakes" of phosphorus kill bacteria and accelerate wound healing

Researchers from the Royal Melbourne Institute of Technology and the University of South Australia have developed an antimicrobial agent based on nanoscale flakes of black phosphorus. When applied to wounds, the nanoparticles kill superbacteria and accelerate skin repair.

Black phosphorus is the most stable modification of phosphorus, consisting of two-dimensional structures resembling graphene in graphite. Thin nanoscale layers of this substance kill microbes by releasing reactive oxygen species.

Researchers tested the safety and effectiveness of black phosphorus nanoflakes on common bacteria that cause hospital-acquired infections. Among other things, the scientists tested the nanoflakes' effect on antibiotic-resistant Staphylococcus aureus (S. aureus), P. aeruginosa (P. aeruginosa) and E. coli (E. coli) bacteria.

Under the influence of black phosphorus, cell viability of Staphylococcus aureus bacteria was reduced by 62% in two hours and by 80% after six hours. After twenty-four hours, the drug killed more than 99% of the bacteria. A similar effect was observed in blue bacillus: in 24 hours phosphorus killed more than 80% of bacteria. At the same time, other cells were not damaged, and the flakes self-decomposed after the infection was eliminated.

The researchers compared the nanoflakes to ciprofloxacin, a popular broad-spectrum antibiotic. In treating wounds in mice infected with Staphylococcus aureus bacteria, both drugs proved effective. But black phosphorus accelerated wound healing and tissue regeneration at macroscopic and microscopic levels compared to the control group. Seven-day therapy resulted in 80% wound closure with no signs of redness or skin damage.

Because of the spread of superbacteria that do not respond to antibiotic therapy, researchers are looking for alternative medicines. Black phosphorus may be one of them. The study authors are planning clinical trials.